I have an intermittant problem with the digital speedo etc readout LCD on my 1992 LT1 that I thought I had fixed by following the procedure on this forum (click "other" at the top of this forum "then tips" then C4 for procedure) but it came back in a few days.
HERE IS THE PROBLEM
The digital dash backlight is nice and bright after I cleaned up the light sensor and when the LCDs are on they are nice and bright.
Intermittantly the LGDs go blank and there is NO information on the center panel.
When this occurs, the high beam light has about 1 sec delay giong out when the headlights are dimmed but otherwise works normally.
When the LCDs are light and the center panel is reading correctly, the high beam indecator does not go off when the headlights are dimmed.
The green indicator lights work corrrectly as they are supposed to (not overly bright) weather the LCDs are working or not so this circuit is not affected.
This problem is obviously an intermittant feed circuit from the CCM, an intermittant groung fault or a bad CCM although all other functions of the CCM are normal.
Has anyone had this type of problem with with their dashboard readouts? Can you shed some light on which circuit I should troubleshoot within the dashboard?
I will have the dashboard out this weekend to install the new white faced guages I bought and would like to cure this annoyance once and for all. I will check the earlier repair to see if this was indeed the fix and it just came loose again.
Will keep the forum posted in the cure if I get it fixed as this seems to be a problem that is popping up on other CF members 1992 as well.
Jerris

 

I am also having the digital cluster go away on my 92. All my signs are pointing to the CCM.

http://forums.corvetteforum.com/show...03&forum_id=82



I recently tried to replace the ECM (cause its easier and cheaper) which hasn't helped. I am trying to avoid the dealer cause I don't have the thousand dollars they are going to want to replace the CCM (which has to be specially programmed).

 

I forgot to say in my post that it is NOT the ECM as I put in a new one 3 weeks ago chasing another problem that was a loose connection on the ICM. For this problem save your money on the ECM.
While the problem could be the CCM as this feeds the LCDs I dont think it is because it is intermittant and problems with the electronics in the CCM dont usually go and come they just die.
Jerris

 

Could be a grounding issue? I'd check the grounds if I knew where they were....

 

It is getting close to the time I will be pulling out the dash again to try and fix this problem once and for all.
Does anyone have any new ideas in this?
Thanks
Jerris

 

ttt